pub fn odd_fibnacci_sum(threshold: u32) -> u32 {
    let mut cnt = 1;
    let mut v:Vec<u32> = vec![0,1];//创建一个vector数组并初始化

    let mut sum = 0;
    while v[cnt]<=threshold {//求小于等于threshold的fibnacci数组并算出其中奇数的和
        if v[cnt]%2==1 {
            sum = sum + v[cnt];
        }
        cnt+=1;
        v.push(v[cnt-1]+v[cnt-2])
    }
    sum
}